Oxygen-linked CO2 transport in sheep blood

1975 ◽  
Vol 229 (2) ◽  
pp. 334-339 ◽  
Author(s):  
R Bauman ◽  
C Bauer ◽  
EA Haller

We have analyzed oxygen-linked carbamate formation in sheep hemoglobin B by measuring a) the effect of CO2 on oxygen affinity and Bohr effect in red cell suspensions and dilute (1.3 mM Hb4) and concentrated (5 mM Hb4) hemoglobin solutions at 37 degrees C and b) CO2 binding curves of deoxygenated and oxygenated whole blood and hemoglobin solutions, respectively, at the same temperature. In the presence of CO2 both the Bohr effect and oxygen affinity were significantly lower in 1.3-mM Hb4 solutions than in either red cell suspensions or 5-mM Hb4 solutions, while in the absence of CO2 Bohr effect and oxygen affinity did not differ significantly in those preparations. Likewise, the fraction of oxygen-linked carbamate obtained from CO2 binding curves was found to be higher in 1.3-mM Hb4 (0.156 M HbCO2/M HbO2) solutions than in 5-mM Hb4 solutions (0.12 M HbCO2/M HbO2) at pH 7.2. We conclude that hemoglobin concentration affects formation of oxygen-linked carbamate. Total oxygen-linked CO2 in sheep whole blood amounted to 0.18 M CO2/M O2 of which 70% is oxygen-linked carbamate. Assuming a respiratory quotient of 0.85, the contribution of oxygen-linked CO2 to carbon dioxide exchange in sheep blood was computed to be 21%.

1981 ◽  
Vol 50 (5) ◽  
pp. 999-1005 ◽  
Author(s):  
J. Qvist ◽  
R. E. Weber ◽  
W. M. Zapol

Oxygen equilibria of whole blood and hemoglobins from adult and fetal Weddell seals are reported. The maternal blood shows a lower O2 affinity than the fetal blood (halfsaturation O2 tension P50 = 26.9 +/- 1.18 and 21.4 +/- 1.25 Torr, respectively, at 37 degrees C and pH 7.4), and a greater Bohr effect (delta log P50/delta pH = -0.49 and -0.31, respectively, at pH 7.4-6.8), correlated with higher red cell 2,3-diphosphoglycerate (2,3-diphosphoglycerate (2,3-DPG) concentrations (6.45 +/- 0.81 mmol.1-1, compared to 2.65 +/- 0-42 mmol.1-1 in the fetus). Both the maternal and fetal erythrocytes contain two major and two minor hemoglobin components occurring in the same ratio and the 2,3-DPG-free whole hemolysates, as well as the isolated major components from each stage, show the same oxygenation properties, ascribing the whole-blood differences to the higher adult DPG levels. A 2,3-DPG effect also appears to account for the disparity in the Bohr effects, which will favor unloading of O2 from the maternal circulation during diving as maternal and fetal blood pH decrease in parallel.


Blood ◽  
1972 ◽  
Vol 39 (3) ◽  
pp. 398-406 ◽  
Author(s):  
Frank G. de Furia ◽  
Denis R. Miller

Abstract Oxygen affinity studies in a splenectomized patient with sporadically occurring Hb Köln disease revealed high whole blood oxygen affinity (P50 O2 17.6 mm Hg) with increased 2, 3-diphosphoglycerate (DPG), low ATP, and normal RBC ΔpH. Isolated electrophoretically slow migrating Hb Köln had a high oxygen affinity, decreased Hill’s number, and normal DPG reactivity. Functional evidence for hybrid tetramers with normal mobility is presented. Partial deoxygenation may play a role in the denaturation of the Hb Köln molecule and thus account for a higher oxygen affinity (low P50 O2), measured by the mixing technique, than the actual values for P50 that exist in vivo. Increased oxygen affinity and decreased P50 O2 would result in increased erythropoiesis and account for a well-compensated hemolytic process in this patient with a normal red cell mass and normal values of hemoglobin.


PEDIATRICS ◽  
1971 ◽  
Vol 48 (6) ◽  
pp. 857-864
Author(s):  
Marcello M. Orzalesi ◽  
William W. Hay

It has been previously shown that red cell 2,3-diphosphoglycerate (DPG) binds to reduced hemoglobin (Hb) decreasing its affinity for oxygen (O2 and that the in vitro effect of DPG on fetal Hb is less marked than on the adult Hb. The present study on whole blood provides evidence that the in vivo effect of DPG on the O2 affinity of fetal Hb is approximately 40% of that of adult Hb. It also shows that the O2 affinity of fetal blood decreases during gestation and depends on the relative proportions of adult and fetal Hb and on the level of red cell DPG.


1963 ◽  
Vol 205 (2) ◽  
pp. 337-340 ◽  
Author(s):  
Peter Hilpert ◽  
Renate Gislinde Fleischmann ◽  
Doris Kempe ◽  
Heinz Bartels

The Bohr effect of the blood and the red cell hemolysates of adult and newborn humans, goats and kids, and sheep and lambs were determined and the physiological significance is discussed. Similar determinations were made on blood from an African elephant, yak, camel, Dybowski deer, and llama. The strong displacement to the right of the oxygen dissociation curve which occurs in kids and lambs during the first 5 days of life can be largely explained by a change in the pH value within the erythrocytes. When the oxygen affinity is expressed by the oxygen pressure necessary for half saturation (T50) at a constant cell pH, considerable differences exist between species.


1982 ◽  
Vol 53 (6) ◽  
pp. 1432-1438 ◽  
Author(s):  
G. K. Snyder ◽  
C. P. Black ◽  
G. F. Birchard ◽  
R. Lucich

Respiratory properties of whole blood during development were studied in embryos of the bar-headed and Canada geese. In both species, affinity of the blood for O2 [expressed as O2 half-saturation pressure (P50)] increased with development, to a low and stable value. The low and stable P50 at pH 7.4 for the bar-headed goose, 20.1 +/- 0.3 Torr, is significantly lower than that for the Canada goose, 26.9 +/- 0.8 Torr. The data suggest a higher Bohr effect for the bar-headed goose. Hill's coefficients, buffering capacity, red cell 2,3-diphosphoglycerate, and blood hemoglobin concentrations are similar in both species. We suggest that the affinity of the whole blood for O2 is an important genetically based adaptation to ensure a high O2 content in the blood in the face of reductions in ambient PO2 associated with nesting at high altitudes. The higher Bohr effect may ensure high tissue PO2 in the presence of the high-affinity hemoglobin.


1979 ◽  
Vol 237 (1) ◽  
pp. H71-H75 ◽  
Author(s):  
P. A. Mueggler ◽  
J. S. Peterson ◽  
R. D. Koler ◽  
J. Metcalfe ◽  
J. A. Black

Hematologic parameters influencing tissue oxygen delivery in dogs during the first 4 mo of life have been investigated. The rapid growth and increase in body temperature during this period imply an increased metabolic rate and increased tissue oxygen demand. Hemoglobin concentration and hematocrit decrease during the 1st mo following birth. The total red cell mass does not decrease during this period. The observed hemodilution can be attributed to an increasing plasma volume in the growing animal. The blood oxygen affinity decreases during this same period, resulting in a more effective tissue oxygen delivery. Erythropoiesis, as estimated from the percent circulating reticulocytes, decreases following birth and does not increase until 1 mo of postnatal life. The increase of erythropoietic activity during the 2nd mo of postnatal life coincides with an increase in red cell mass, hematocrit, and hemoglobin concentration.


1991 ◽  
Vol 156 (1) ◽  
pp. 399-406
Author(s):  
R. L. Ingermann ◽  
N. J. Berner ◽  
F. R. Ragsdale

The oxygen affinity of red cell suspensions from fetal garter snakes was higher than that of cell suspensions from their mothers. This difference appeared to be due to different concentrations of nucleoside triphosphate (NTP, primarily adenosine triphosphate). NTP concentrations were significantly higher, and oxygen affinities were significantly lower, in red cell suspensions from pregnant females compared with those from nonpregnant females or males; there is no precedent for such a pronounced effect of pregnancy on the oxygen affinity of maternal blood. These data indicate that pregnancy may result in an enhanced ability of adult blood to deliver oxygen to the fetus. Since the binding of organic phosphates and oxygen to hemoglobin is sensitive to temperature, and since these animals experience diurnal changes in temperature, we examined the influence of relatively low (20 degrees C) and high (34 degrees C) temperatures on red cell oxygen-affinity. The temperature increase of 14 degrees C resulted in a lowered oxygen-affinity of all red cell suspensions examined. However, this increase in temperature lowered the affinity of maternal red cells to a greater extent than it did the affinity of fetal red cells. This suggests that daytime temperatures may further enhance the ability of maternal blood to deliver oxygen to the fetus at times when fetal oxygen demand is probably greatest.


1979 ◽  
Author(s):  
G Cella ◽  
H de Haas ◽  
M Rampling ◽  
V Kakkar

Haemorrheological factors have been shown to be affected in many kings of vascular disease. The present study was undertaken to correlate these factors in normal subjects and patients suffering from peripheral arterial disease. Twenty-two patients were investigated; they had moderate or severe intermittent claudication, extent of disease being confirmed by aorto-arteriography and ankle-systolic pressure studies. Twenty-five controls with no symptoms or signs of arterial disease were selected with comparable age and sex distribution. Whole blood viscosity was measured at shear rates of 230 secs-1 and 23 secs-lat 37°c using a Wells Brookfield cone plate microvisco meter. Plasma viscosity was also measured in an identical manner. Erythrocyte flexibility was measured by centrifuge technique and fibrinogen concentration as well as haematocrit by standard techniques. The fibrinogen concentration appeared to be the only significant parameter; the mean concentration in patients with peripheral vascular disease of 463 ± 73mg/l00ml in the control group ( < 0.05). Although whole blood viscosity was high in patients, when corrected to a common haematocrit, there was no significant difference between patients and controls. The same megative correlation was found for plasma viscosity. The red cell flexibility was found to be increased in patients as compared to the control group, but this effect appeared to be simply proportional to the fibrinogen concentration.


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